1. Technical Field
The present invention relates to a compound machining center capable, of carrying out a compound machining including turn broaching working and turning working, and also relates to a compound machining method and a machine tool. And the present invention further relates to a compound machining center capable of working both ends of a work having a shaft shape by one working machine.
2. Prior Art
In a known art, many kinds of shaft-shaped works (called merely work or works herein) are subjected to turning (roughing) working by using a turning machine such as lathe, and in the prior art, in order to carry out a finishing working continuously after the roughing working, there is known a turret lathe to which a plurality of tools are mounted and by which a work is worked while sequentially changing (exchanging) the tools.
Furthermore, there is known a turn broaching machine as a machine or tool for continuously working the work from the roughing to the finishing.
Such known broaching machine comprises a broaching tool having a disc shape or linear shape and a plurality of (working) tips which are adapted to work the work from the roughing working to the finishing working and which are mounted and arranged to the disc-shaped broaching tool in the circumferential direction thereof or to the linear-shaped broaching tool in the linear direction thereof with a space from each other. The broaching tool is rotated or linearly moved in the tangential direction, while rotating the work, to thereby carry out the turning working and the turn broaching working by means of tips.
However, in the conventional turret lathe, it is required for the turret to have a large size for mounting a plurality of tools, which requires much installation space and, hence, the machine itself is made large and expensive, thus being inconvenient and disadvantageous.
Furthermore, in the conventional broaching machine, since it is necessary to use the large disc-shaped or linear-shaped broaching tool provided with a plurality of tips, as like as the turret lathe mentioned above, a large sized and expensive broaching machine is required. Moreover, since the broaching tool is itself large and heavy, much time and labor are required for an operator to exchange the tools, and in such tool exchanging time, the operation or working of the machine is interrupted, thus being also inconvenient and disadvantageous in productivity, for example.
Incidentally, for example, Japanese Patent Laid-open Pub. Nos. S 63-196315, 63-196316 and S 63-237810 disclose a turning machine for carrying out a turning working to a work while linearly moving a tool.
However, according to the known structures of such publications, the tool is moved linearly only in a direction normal to the axis of the work having shaft shape to carry out the broaching working to the work, and hence, it is impossible to lathe the work while moving the tool in the longitudinal direction of the shaft-shaped work. Therefore, types or kinds of the works to be worked by such turning machine are limited, thus being inconvenient and not practical in use.
Still furthermore, in the prior art, when a shaft-shaped work such as crankshaft is worked by a turning machine such as lathe, there has generally been adopted a method of lathing the work by supporting one end portion of the work by a tail stock center and clamping the other one end portion by a chuck through which the work is rotated.
However, in this known method, the end portion clamped by the chuck cannot be worked. In order to obviate this defect, in the prior art, two turning machines are preliminarily prepared. The entire portion of the work except for the end portion clamped by the chuck is worked by one turning machine and, then, the work is transferred to the other turning machine by which the unworked end portion, which has been clamped by the chuck, is worked.
In a general turning machine, however, the chuck and driving means are disposed on a left side and the tail stock is installed on a right side. Therefore, when both the end portions of the work is worked by using two turning machines, it is necessary to turn, by 180xc2x0, the work one end portion of which has been worked by the first turning machine and to mount the work to the second turning machine. For such operation, there is required, a work inverting mechanism provided for the conveying means such as autoloader for conveying the work between the turning machines. Thus, the work conveying means is made complicated in its structure and is made expensive.
Still furthermore, the location of two turning machines at the working line will involve an increased equipment cost and require much space for installation, thus being inconvenient and defective.
To eliminate this defect, Japanese Patent Pub. No. S 61-3604 shows a crankshaft turning machine.
In this crankshaft turning machine, both the end portions of the crankshaft are supported by tail stocks and the intermediate portion thereof is grasped by a grasping member, and the work turning working is carried out by a work driving device while rotating the work.
By the crankshaft turning machine disclosed in the above prior art publication, however, both the end portions of the work can be worked, but the intermediate portion thereof grasped by the grasping member cannot be worked and this intermediate portion should be worked thereafter by another turning machine, which hence requires a plurality of turning machines, involving the increased equipment cost.
Furthermore, a work such as crankshaft has usually both end portions having different shapes, so that the turning (working) conditions are different. Accordingly, when the work is worked by the turning machine mentioned above, since the work is rotated by the single work driving device, it is difficult to turn and cut both the end portions at suitable turning speeds at the times of turning the work with the different working conditions, respectively and hence, it is difficult to carry out the working at a precise performance.
An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art mentioned above and to provide a compound machining center in which a turn broaching working for working a work (workpiece) is performed by linearly moving a tool in a tangential direction of the work while rotating the work and a turning working for turning the work is performed by moving the tool in the direction normal to the axis of the work while rotating the work, independently or in combination, and also provide a compound machining method and a machining tool for the machining center.
Another object of the present invention is to provide the compound machining center, the machining method and the machining tool for improving productivity of works each having a shaft-like long scale by using one turning machine by which the turning working of both end portions of the work can be effectively performed.
These and other objects can be achieved according to the present invention by providing, in one aspect, a compound machining center comprising:
a work driving unit, including a chuck, mounted on a bed and adapted to rotate a work to be worked in a state of the chuck grasping one end of the work;
a tail stock center mounted on the bed and adapted to support the other one end of the work so as to support the work on a working axial line between the tail stock center and the chuck of the work driving unit;
a working unit disposed on the bed to be movable in an X-axis direction parallel to the working axis line and a Y-axis direction normal to the X-axis direction by X-axis driving means and Y-axis driving means; and
a tool mounted to the working unit to be linearly movable in a tangential direction of the work by Z-axis driving means to thereby carry out turning working and turn broaching working.
In another aspect, there is also provided a compound machining center comprising:
a pair of work driving units, each including a chuck, mounted on a bed and adapted to rotate a work to be worked in a state of the chucks grasping both ends of the work so as to support the work on a working axis line;
a pair of working units disposed on the bed to be movable in an X-axis direction parallel to the working axis line and a Y-axis direction normal to the X-axis direction by X-axis driving means and Y-axis driving means; and
tools mounted to the working units to be linearly movable in a tangential direction of the work by Z-axis driving means to thereby carry out turning working and turn broaching working.
According to the above one and another aspects, the tools can be made compact in comparison of the use of conventional turret lathe, turn broaching apparatus or like, and the machining center is hence itself made compact, reducing manufacturing cost or equipment cost, and the tools can be exchanged with in a short time, improving the productivity.
Furthermore, since a plurality of tips are arranged linearly, an interval between adjacent tips can be made small, reducing a tip indexing time and improving the productivity. Moreover, in a case where the tips are exchanged with the tools being mounted to the machining body at a time when the tips are worn or damaged, the tips can be exchanged with in a short time because of a small interval therebetween.
In preferred embodiments of the above aspects, the tool is linearly moved by the Z-axis driving means in a vertical direction in a state that the working unit is placed on the bed, or the tool is linearly moved by the Z-axis driving means in an obliquely vertical direction in a state that the working unit is placed on the bed.
According to this arrangement, since the linear movement of the tool in the Z-axis direction can be made smooth and accurately, the working precision can be improved.
In a further aspect of the present invention, there is provided a tool for carrying out turning working and turn broaching working to a work to be worked, mounted, to be linearly movable in a tangential direction of the work, to a working unit which is movable in at least one of X-axis direction and Y-axis direction normal to the X-axis direction, the tool comprising:
a tool body;
a turning working tip mounted to the tool body for carrying out turning working to the work while moving the tool in at least one of the X-axis direction and Y-axis direction normal to the X-axis direction without linearly moving the tool in the tangential direction of the work; and
a turn broaching working tip mounted to the tool body for carrying out turn broaching working to the work while linearly moving the tool in the tangential direction of the work.
The turning working tip and the turn broaching working tip are arranged linearly on the tool body.
According to this further aspect, the turning working is carried out by the turning working tip mounted to the tool body while rotating the work and moving the work driving unit in at least one of the X-axis direction and Y-axis direction normal to the X-axis direction, and the turn broaching working is carried out by the turn broaching working tip while linearly moving the tool in the tangential direction of the work, so that the turning working and the turn broaching working can be performed by one machining center. Thus, the machining center can be made compact and can be widely and generally utilized.
In a still further aspect of the present invention, there is provided a compound machining method comprising:
a step of preparing a tool provided with a plurality of turning working tips and at least one turn broaching working tip, which are arranged linearly to the tool;
a turning working step in which the tool is linearly moved in a tangential direction of a work to be worked, to position the turning working tips of the tool to a working position, and the work is subjected to the turning working by the turning working tips while rotating the work and moving the tool in at least one of X-axis direction and Y-axis direction normal to the X-axis direction; and
a turn broaching working step in which the tool is indexed to a broaching working position in an axial direction of the work and the work is then subjected to the turn broaching working by the turn broaching working tip of the tool while rotating the work and linearly moving the tool in the tangential direction of the work,
wherein the turning working step and the turn broaching working step are carried out independently or in combination thereof to thereby carry out a compound machining working to the work.
According to the above embodiment, since both the turning working and turn broaching working to the work can be carried out by the single (one) machining center, it is not necessary to independently arrange the turning machine and the broaching machine or like, so that the construction cost or equipment cost can be significantly reduced. Moreover, since the turning working and the turn broaching working can be continuously carried out, the productivity can be improved.
In a still further aspect of the present invention, there is provided a compound machining center comprising:
a pair of work driving units, each including a chuck, mounted to a common bed in a state that both the chucks are opposed to each other, each of the chucks grasping one end of each of works to be worked for rotating the works;
a pair of tail stock centers, each including a center member, disposed between the work driving units in a state that the center members are opposed to the chucks respectively, each of the center members supporting other end of each of the works, the tail stock centers and the work driving units constituting a first work station and a second work station so as to support both the works on same working axis line;
a plurality of working units mounted on the common bed to be movable in an X-axis direction parallel to the working axis line and a Y-axis direction normal to the X-axis direction; and
a plurality of tools detachably mounted to the working units respectively for working the works.
In a still further aspect of the present invention, there is also provided a compound machining center comprising:
a pair of tail stock centers, each including a center member, mounted to a common bed in a state that both the centers are opposed to each other, each of the center members supporting one end of each of works to be worked;
a pair of work driving units, each including a chuck, disposed between said tail stock centers in a state that the chucks are opposed to the center members respectively, each of the chucks grasping other one end of each of the works, the work driving units and the tail a stock centers constituting a first work station and a second work station for rotating and driving both the works on same working axis line;
a plurality of working units mounted on the common bed to be movable in an X-axis direction parallel to the working axis line and a Y-axis direction normal to the X-axis direction; and
a plurality of tools detachably mounted to the working units respectively for working the works.
According to the above still further aspects, both the end portions of the long-scaled work such as crankshaft can be worked by the single turning machine, and hence, it is not necessary to arrange two turning machines on the working line, thus largely reducing the equipment cost or like, and the machine can be installed in a small space.
Furthermore, since the work driving units provided with the chucks, each for grasping one end of the work, disposed on both end sides of the bed, the work which has been worked in the first work station can be conveyed to the second work station without rotating the work by 180xc2x0 to carry out the further working. Thus, no inverting motion is required to convey the work to the second work station from the first work station, so that the work conveyance can be smoothly performed between the respective work stations.
Still furthermore, according to these aspects, since the work driving units are mounted independently to the first and second work stations, both the end portions of the work such as crankshaft having different forms so as to be worked on the different conditions, can be worked at the same time on the different working (cutting) conditions at the first and second work stations. Accordingly, the working time can be significantly shortened in comparison with the conventional working process in which the work end portions are worked separately, thus improving the productivity.
In preferred embodiments of the above aspects, the tools are mounted to the working units to be movable linearly in a vertical (Z-axis) direction in a state mounted on the common bed, and each of the tools comprising: a tool body; a turning working tip mounted to the tool body for carrying out turning working to the work while moving the tool in at least one of the X-axis direction and Y-axis direction without linearly moving the tool in the Z-axis direction; and a turn broaching working tip mounted to the tool body for carrying out turn broaching working to the work while linearly moving the tool in the Z-axis direction.
The tools may be mounted to the working units to be movable linearly in an obliquely vertical direction in a state mounted on the common bed, and each of the tools comprising: a tool body; a turning working tip mounted to the tool body for carrying out turning working to the work while moving the tool in at least one of the X-axis direction and Y-axis direction without linearly moving the tool in the obliquely vertical direction; and a turn broaching working tip mounted to the tool body for carrying out turn broaching working to the work while linearly moving the tool in the obliquely vertical direction.
According to such preferred embodiments, the turning working is carried out by the turning working tip mounted to the tool body while rotating the work and moving the working units in at least one of the X-axis direction and Y-axis direction normal to the X-axis direction, and the turn broaching working is carried out by the turn broaching working tip while linearly moving the tool in the tangential direction of the work, so that the turning working and the turn broaching working can be performed by one machining center. Thus, the machining center can be made compact, and can be widely and generally utilized.
In a further preferred embodiment, the tools are circular broaching tools mounted to the working units to be rotatable, each of the tools comprising: a tool body; a turn broaching working tip mounted to the tool body for carrying out turn broaching working to the work while rotating the circular broaching tool; and a turning working tip for carrying out turning working to the work while moving the working units in at least one of the X-axis direction and Y-axis direction without rotating the circular broaching tool.
According to this preferred embodiment, the turning working is carried out by the turning working tip mounted to the tool body while rotating the work and moving the working units in at least one of the X-axis direction and Y-axis direction normal to the X-axis direction, and the turn broaching working is carried out by the turn broaching working tip while rotating the broaching tool and moving the turn broaching working chip in the tangential direction of the work, so that the turning working and the turn broaching working can be performed by one machining center. Thus, the machining center can be made compact, can be widely and generally utilized. Furthermore, it is possible to mount a number of tips to the broaching tool, so that the tool exchanging frequency due to the tip wearing or tip damage will be reduced, and hence, the working performance of the machining center can be improved, resulting in the improved productivity.
Furthermore, the machining center may further comprises a work conveying means for conveying the works to the respective work stations.
According to this embodiment, the work which has been machined at the first work station can be promptly conveyed to the second work station without reversing the work in conveying the work, so that the work conveying means comprises no work reversing means and thus can be made compact and the working line can be prepared with reduced installation cost.
The nature and further characteristic features of the present invention will be made more clear from the following descriptions made with reference to the accompanying drawings.